Drinks containing cochineal colorant and method of preventing discoloration thereof

ABSTRACT

The present invention provides a cochineal pigment-containing beverage comprising nigerooligosaccharide and an anti-fading method for a cochineal pigment-containing beverage comprising adding thereto nigerooligosaccharide.

This application claims benefit under 35 U.S.C. 371 of PCT/JP00/05169,filed Aug. 2, 2000.

TECHNICAL FIELD

This invention relates to an anti-fading method for a beverage coloredwith a cochineal pigment and to a cochineal pigment-containing beverageprevented from losing colors.

BACKGROUND ART

Various pigments have conventionally been used to enhance the preferenceof foods and drinks and especially consumer needs for natural pigmentsare recently on the rise. Among the natural pigments, berry color, redcabbage color, grape skin color and like anthocyanin pigments providingorange-to-red color have been conventionally and widely used as foodcolorants. However, the anthocyanin pigments have serious defects tofade or discolor when exposed to light rays. In contrast, cochinealpigments, also providing orange-to-red colors (under acidic conditions),are known to be excellent especially in light resistance among thenatural pigments and widely used for coloring foods and drinks showingacidity.

However, even the above cochineal pigment is not satisfactory in lightresistance and gradually fades with prolonged exposure to light.Further, recently clear colorless glass and PET bottles are preferred ascontainers. Foods and drinks packed in such containers are oftenexhibited for sale under harsh conditions as exposed to light for 24hours, for example, at convenience stores, so that complaints againstdiscolored products are increasing. In view of these situations,development of a new agent or a new method is strongly desired in therelated industrial areas for preventing fading or discoloring of thenatural pigments.

Accordingly, an object of the present invention is to provide a novelanti-fading agent capable of preventing a cochineal pigment from fading,an anti-fading method for a cochineal pigment-containing beverage, and acochineal pigment-containing beverage protected from discoloration.

The inventors have conducted extensive researches to achieve the aboveobject and found that a certain type of sugar existing in the well-knownand widely-used food material of carbohydrate is effective in preventingfading of a cochineal pigment caused by exposure to light, to therebyaccomplish the present invention.

DISCLOSURE OF INVENTION

The present invention provides a cochineal pigment-containing beveragecomprising nigerooligosaccharide.

Beverages of the invention include a beverage comprising 0.02 to 10.8 gof nigerooligosaccharide per mg of cochineal pigment; a beveragecomprising 1 to 20 mg of cochineal pigment and 1 to 15 g of a syrupcontaining 40 to 72% by weight of nigerooligosaccharide per 100 ml ofthe beverage; and beverages containing the above components in which pHis adjusted to 5 or below and which additionally comprise vitamin C anddietary fibers.

Further, the present invention provides an anti-fading method forcochineal pigment-containing beverage comprising incorporatingnigerooligosaccharide, in more detail, an anti-fading method for abeverage comprising adding 0.02 to 10.8 g of nigerooligosaccharide permg of cochineal pigment; an anti-fading method for a beverage comprisingincorporating 1 to 20 mg of cochineal pigment and 1 to 15 g of syrupcontaining 40 to 72% by weight of nigerooligosaccharide per 100 ml ofthe beverage; and an anti-fading method for beverages comprisingadjusting the pH of beverage to 5 or below and incorporating vitamin Cand dietary fibers in addition to the above ingredients.

By addition of nigerooligosaccharide, the cochineal pigment-containingbeverage of the invention can be effectively protected for a long timefrom fading of the cochineal pigment caused by exposure to light. Asseen from the examples given below, for example, a cochinealpigment-containing beverage fades and becomes almost transparent andcolorless when exposed to 20,000 lux(Lx) fluorescent light for aboutthree weeks, while a cochineal pigment-containing beverage comprisingnigerooligosaccharide in about seven-hundredfold parts by weight per onepart weight of cochineal pigment exhibits such an excellent anti-fadingeffect that the beverage does not substantially discolor after about twomonths under the same conditions.

The beverages of the invention as hereinafter explained in detail, arenot limited and may be any known type containing a cochineal pigment.The beverages encompass any type of soft drinks including fruit juices,carbonated beverages, etc. The beverages are preferably bottled in lightpermeable containers such as clear glass bottles, clear colorless PETbottles and the like.

A beverage according to a preferable embodiment of the present inventioncontains the following ingredients in the total amount of 100 ml.

Nigerooligosaccharide-containing syrup 1-15 g Cochineal Pigment 1-20 mgSaccharide 1-20 g Dietary Fibers 10 g or less Sour agent 0.1-2 gFlavoring agent proper quantity Fruit juices proper quantity Vitaminsproper quantity Minerals proper quantity Amino-acids proper quantityHigh-intensity sweetener proper quantity

Examples of the high-intensity sweetener include stevia (stevioside),suclarose or the like.

The general term “cochineal pigment” is used herein to mean a class ofpigments comprising carminic acid as an active ingredient and may be anypigment used as coloring agent in the field of drugs or foods. Thecochineal pigment may be used in the invention in commercially availableforms, such as powder, solution, etc. Examples of commercially availableproducts include “SAN RED No.1” (San-Ei Gen F.F.I.,Inc), “RED NY-C”(Japan Chlorophyll Co.,Ltd), “kidrenin” (Tokyo Tanabe Seiyaku Co.,Ltd.), “DAIICHI COLOR RED RC” (Daiichi Kasei Co.,Ltd), “RED COLOR TH-C”(T. Hasegawa Co., Ltd), etc.

The cochineal pigment-containing beverage of the present inventioncontains the cochineal pigment preferably in an amount of 1 to 20 mg,more preferably in an amount of about 1 to about 2 mg per 100 ml of thebeverage.

According to the invention, it is essential to incorporatenigerooligosaccharide into the beverage. The general term“nigerooligosaccharide” is used herein to mean oligosaccharides with adegree of glucose polymerization of 2 or more and containing at leastone alpha-1, 3-glucosidic linkage. Nigeroologosaccharides preferably areoligosaccharides with a degree of glucose polymerization of 2 to 10, andmore preferably are oligosaccharides with a degree of glucosepolymerization of 2 to7. Examples of such nigerooligosaccharides arenigerose, nigerosylglucose, nigerosylmaltose and the like. Thenigerooligosaccharide as an anti-fading agent in the present inventionincludes oligosaccharides having only alpha-1, 3-glucosidic linkages aswell as oligosaccharides having alpha-1, 3-glucosidic linkages and otherglucosidic linkages (for example, alpha-1, 1-, alpha-1, 2-, alpha-1, 4-,and alpha-1, 6-glucosidic linkages).

Nigerooligosaccharide can be produced by any method. For example, it canbe prepared by the known method (for example, M. Stacey and J. M.Webber: Methods in Carbohydrate Chemistry, I, pp.339-341, Academic press1962). More specifically, the method comprises the step of hydrolysing amicroorganisms-produced polysaccharide such as nigeran, erucinan and thelike as a substrate by using an enzyme or an acid. Another method isknown which employs the known transglycosylation and/or condensationreaction of alpha-glucosidase to produce nigerose (see Ken-ichi Kaneyaet al., The Society of Japan Agricultural Chemistry, 53, pp. 385-390,1979; H. Fujimoto et al., Agric. Biol. Chem., 52, pp. 1345-1351, 1988;etc.). Unexamined Japanese Patent Publication No. H03-22958 disclosesanother method, wherein a cyclodextrin glucanotransferase is used to acton a starch hydrolyzate to produce nigerose. Further, another method isdisclosed (Unexamined Japanese Patent Publication No. H07-59559),wherein at least one of glycosyltransferases providing alpha-1,3-linkage, specifically, a glycosyltransferase which is obtained byconventionally culturing fungi which belongs to the genus Acremonium andproduces a glycosyltransferase providing alpha-1, 3-linkage, forexample, Acremonium sp. S4G13 (FERM BP-4373), is allowed to act on asubstrate containing an alpha-1, 4-glucoside-linked polysaccharide oroligosaccharide to produce nigerooligosaccharide.

The nigerooligosaccharide used in the invention as an anti-fading agentfor a cochineal pigment can be prepared by any method selected fromthose mentioned above. However, the method using glycosyltransferase(nigerooligosaccharide glucanotransferase) disclosed in UnexaminedJapanese Patent Publication No. H07-59559 is considered the mosteconomical among known methods. Therefore, the nigerooligosaccharideprepared by this method is preferably used in the invention.

The cochineal pigment-containing beverage of the present inventioncontains nigerooligosaccharide as essential ingredient and may containvarious optional ingredients producing no adverse effect on theanti-fading action. The saccharides (syrup) prepared by the methodmentioned above may contain monosaccharides like glucose,oligosaccharides comprised of other glucosidic linkages than alpha-1,3-glucosidic linkage (such as maltose), dextrin, and the like, inaddition to an oligosaccharide (nigerooligosaccharide) with a degree ofglucose polymerization of 2 or more which contains at least one alpha-1,3-glucosidic linkage, such as nigerose, nigerosylglucose,nigerosylmaltose and the like. Such syrup as containingnigerooligosaccharide and any other ingredients is usable in theinvention as it is. Nigerooligosaccharide consisting only of nigerose isusable. Nigerooligosaccharide used as an anti-fading agent in thepresent invention may be in the form of a mixture ofnigerooligosaccharides with different degrees of glucose polymerization,and if necessary, it may be a single nigerooligosaccharide with arequired degree of glucose polymerization separated by the method suchas chromatographic fractionation. The anti-fading agent may be in theform of syrup obtained by the above-mentioned methods or in any otherform such as freeze-dried powders, powders, granules, etc.

In producing the beverage of the invention, nigerooligosaccharide may beincorporated together with the ingredients of the base beverage or maybe added after producing the base beverage, so that these components maycoexist with a cochineal pigment in the resultant beverage.

The amount of nigerooligosaccharide to be included in the beverage ofthe invention may basically be such an amount capable of achievinganti-fading effect, and is suitably determined depending on the type andamount of the ingredients contained in the beverage, especially the typeand amount of cochineal pigment, the type of the beverage, etc. Usually,the amount of nigerooligosaccharide is in the range of 0.02 to 10.8 g,preferably in the range of about 0.5 to about 2.0 g per 1 mg ofcochineal pigment. The above amount of nigerooligosaccharide correspondsto about 1 to about 15 g, preferably about 1.2 to about 4.5 g of thesyrup containing 40 to 72% by weight of nigerooligosaccharide per 100 mlof the beverage.

Beverages of the present invention may be adjusted to pH 5 or below andmay contain vitamin C and dietary fibers in specified amounts. The pHcan be adjusted, for example, by adding a sour agent such as citricacid, etc. Since cochineal pigments are known to have higher stabilityand show better color tone under acidic condition than other pigmentsand widely used under the acidic condition. Soft drinks are usuallyacidic and therefore the invention can favorably be applicable to acidicdrinks.

Conventionally, it is considered care must be taken when vitamin C anddietary fibers are added to a cochineal pigment-containing beveragebecause both of them generally tend to promote fading of a cochinealpigment. However, according to the present invention, these ingredientscan be safely included in the beverage due to the excellentfading-preventive action of nigerooligosaccharide.

Any known dietary fibers generally added to this type of beverage, suchas polydextrose, pinefiber and the like are usable.

The amounts of vitamin C and the dietary fibers may generally be, per100 ml of the beverage, up to about 1 g and up to about 10 g,respectively.

According to the invention, the desired cochineal pigment-containingbeverages can be obtained, which are remarkably prevented or protectedfrom fading of a cochineal pigment conventionally caused by exposure tolight. These beverages have good appearance of reddish orange tone andhave good taste. Further, the vitamin C and dietary fiber-containingbeverage of the invention is beneficial from the viewpoint of dietetics.

BEST MODE FOR CARRYING OUT THE INVENTION

The following examples are given to illustrate the present invention.Examples 1-3

Cochineal pigment-containing beverages of the present invention wereprepared, using nigerooligosaccharide-containing syrup (trade name:Taste Oligo, product of Nihon Shokuhin Kako Co., Ltd.,nigerooligosaccharide content: 43.5% by weight, solid content: 73% byweight) and other ingredients given in Table 1 below. Table 1 shows alsoa composition of comparative cochineal pigment-containing beverage thatdoes not contain nigerooligosaccharide-containing syrup.

TABLE 1 Ingredients Comp. (/100 ml) Example 1 Example 2 Example 3Example Nigerooligo- 1.4 2.8 4.3 0 saccharide- (No addition) containingSyrup (g) Sugar (g) 5.8 5.1 4.5 6.4 Liquid sugar 5 5 5 5 (g) DietaryFiber 7 7 7 7 (g) Sour agent small small small small (g) quantityquantity quantity quantity Vitamin C (mg) 300 300 300 300 Cochineal 1.681.68 1.68 1.68 Pigment (mg)

Polydextrose was used as “dietary fiber” in all beverages shown in Table1, and each beverage had a pH of 3.

Experiment 1

Each of clear colorless glass bottles (capacity: 100 ml) was filled witheach of the cochineal pigment-containing beverages of the inventionprepared in Examples 1-3 and the comparative beverage to make testsamples. A set of these test samples was exposed to sunlight (in a smallroom having a glass window on the south side) and another set of thesesamples was exposed to a fluorescent light (Growth Cabinet MLR-350,SANYO Electric Co., Ltd, illumination: 20,000 Lux), and thediscoloration of bottled beverages with time was observed.

The degrees of fading were evaluated by measuring the absorbance at amaximum absorption of 490 nm of cochineal pigment and calculating thecolor persistency (%) using the absorbance (reference) at the time ofstarting the test (at the time of starting the irradiation with sunlightor fluorescent light) and the absorbance after prescribed time.

The degrees of fading were evaluated by measuring the absorbance at amaximum absorption of 490 nm of cochineal pigment and calculating thecolor persistency (%) according to the following equation, using theabsorbance (reference) at the time of starting the test (at the time ofstarting the irradiation with sunlight or fluorescent light) and theabsorbance after prescribed time.

Results are shown in Table 2 (sunlight irradiation) and in Table 3(fluorescent light irradiation). The time of exposure to sunlight inthese test is expressed in solar radiation unit (MJ/m²) which wasdetermined by Solar Cell Actinometer SA-T-300 (Suga Test InstrumentsCo., Ltd.). Usually, solar radiation per sunny midsummer day isestimated to be at about 20 MJ/m².

TABLE 2 persistency Comp. (%) Example 1 Example 2 Example 3 Example atthe time 100.0 100.0 100.0 100.0 of starting the test at 90 MJ/m² 91.6394.70 94.23 82.68 at 370 MJ/m² 58.25 87.53 90.90 34.59 at 740 MJ/m²25.48 47.49 75.81 22.53

TABLE 3 persistency Comp. (%) Example 1 Example 2 Example 3 Example atthe time 100.0 100.0 100.0 100.0 of starting the test after 1 week 95.2895.55 97.66 91.53 after 2 weeks 90.04 95.92 96.91 48.04 after 3 weeks84.43 93.39 95.17 35.34

As is apparent from Table 2 and Table 3, the cochinealpigment-containing beverage of the present invention is effectivelyinhibited from fading caused by exposure to light in relation to theconcentration of nigerooligosaccharide.

What is claimed is:
 1. A cochineal pigment-containing beveragecomprising a cochineal pigment containing beverage and anigerooligosaccharide.
 2. A beverage according to claim 1, whichcontains 0.02 to 10.8 g of nigerooligosaccharide per mg of cochinealpigment.
 3. A beverage according to claim 1, which contains 1 to 20 mgof cochineal pigment and 1 to 15 g of syrup containing 40 to 72% byweight of nigerooligosaccharide per 100 ml of the beverage.
 4. Abeverage according to any one of claims 1 to 3, which is adjusted to pH5 or below and containing vitamin C and dietary fibers.
 5. Ananti-fading method for a cochineal pigment-containing beveragecomprising adding to the cochineal pigment-containing beveragenigerooligosaccharide to prevent fading of the pigment in the beverage.6. An anti-fading method for beverage according to claim 5, whereinnigerooligosaccharide is added in an amount of 0.02 to 10.8 g per mg ofcochineal pigment.
 7. An anti-fading method for beverage according toclaim 5, wherein 1 to 20 mg of cochineal pigment and 1 to 15 g of syrupcontaining 40 to 72% by weight of nigerooligosaccharide are added per100 ml of the beverage.
 8. An anti-fading method for beverage accordingto any one of claims 5 to 7 wherein the pH of said beverage is adjustedto 5 or below and further adding vitamin C and dietary fibers.